I'm having a hard time understanding why no one sees why this child is in great danger to himself and those around him. While we can't diagnosis over the internet, it sounds to me as if he might have bipolar disorder in addition to Autism Spectrum Disorders (ASD). The hypersexuality, self-harming behaviors and aggression are all symptoms of BiPolar (BP). According to The Bipolar Child by Demitri and Janice Papolos, at least 10 precent of children with Autism Spectrum Disorders (ASD) have a bipolar comorbidity. And it may actually be a higher percentage (in the 35 percent range). If he has BiPolar (BP), that would mean treatment with mood stabilizers and atypical antipsychotics. I'm not sure if you're already gone that route with your difficult child.
I think you're going to have to listen to Marg on the next steps to take since she's the one who knows how your country's health care system works. Sending many gentle hugs your way.
